https://doi.org/10.1140/epjqt/s40507-018-0066-3
Research
Quality factor of a transmission line coupled coplanar waveguide resonator
1
National University for Science and Technology (MISiS), Moscow, Russia
2
National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow, Russia
* e-mail: ilia.besedin@gmail.com
Received:
3
October
2017
Accepted:
12
January
2018
Published online:
22
January
2018
We investigate analytically the coupling of a coplanar waveguide resonator to a coplanar waveguide feedline. Using a conformal mapping technique we obtain an expression for the characteristic mode impedances and coupling coefficients of an asymmetric multi-conductor transmission line. Leading order terms for the external quality factor and frequency shift are calculated. The obtained analytical results are relevant for designing circuit-QED quantum systems and frequency division multiplexing of superconducting bolometers, detectors and similar microwave-range multi-pixel devices.
Key words: coplanar waveguide / microwave resonator / conformal mapping / coupled transmission lines / superconducting resonator
© The Author(s), 2018